Reduced acromiohumeral distance and increased critical shoulder angle: implications for primary care clinicians

Investigating the Role of Symptom Duration and Critical Shoulder Angle in Predicting Acromiohumeral Interval Reversibility in Patients With Massive Rotator Cuff Tears

Background

Acromiohumeral interval (AHI) reversibility is used to evaluate whether superior humeral migration is fixed or flexible in patients with massive rotator cuff tears (MRCTs). AHI reversibility is measured as the difference in the AHI observed between standard and stress radiography. However, factors affecting AHI reversibility have not been studied in the existing literature.

Purpose

To investigate potential factors affecting AHI reversibility in patients with MRCTs.

Study Design

Case-control study; Level of evidence, 3.

Methods

A retrospective analysis was conducted on 58 patients with MRCTs, who had undergone magnetic resonance imaging, computed tomography, and stress radiography of the same shoulder. Potential factors affecting AHI reversibility were evaluated by stepwise regression analysis.

Results

A total of 58 patients (26 male, 32 female) were included in this study. The mean age of the patients was 66.4 ± 8.3 years. There were 33 patients classified as having a reversible AHI and 25 patients classified as having an irreversible AHI. Age, time from symptom onset, anteroposterior tear size, critical shoulder angle (CSA), acromial index, and subscapularis Goutallier grade were associated with AHI reversibility in univariate analysis. Multivariate linear regression analysis showed that a longer time from symptom onset and a bigger CSA were significantly associated with lower AHI reversibility. No significant association was found between AHI reversibility and sex; body mass index; activity level; tear retraction; biceps condition; deltoid cross-sectional area; and Goutallier grade of the supraspinatus, infraspinatus, and teres minor muscles. The cutoff values to predict AHI reversibility for time from symptom onset and CSA were found to be 5.5 years and 38°, respectively.

Conclusion

Time from symptom onset (>5.5 years) and CSA (>38°) were significant independent factors of AHI reversibility. These factors should be considered for the decision-making process in patients with MRCTs.

The Critical Shoulder Angle Can be Accurately and Reliably Determined from Three-Dimensional Computed Tomography Images

OBJECTIVE

Anteroposterior (AP) radiographs do not necessarily offer the optimal approach to measuring the critical shoulder angle (CSA) due to the malposition of the scapula. Three-dimensional computed tomography (3D-CT) may offer some advantages, including the ability to rotate the scapula for position alignment and pre-operative planning for reducing CSA. This study aimed to investigate the accuracy and reliability of CSA measurement in 3D-CT and to determine whether there is an association between CSA and rotator cuff tears (RCTs).

METHODS

In this retrospective study we identified 200 patients who received shoulder arthroscopy from 2019 to 2021, including 142 patients (81 females, 61 males) with RCTs and 58 patients (14 females, 44 males) with non-RCTs. For each participant, CSA was measured from standard shoulder AP radiographs and anterior views of 3D-CT of the scapula by two independent assessors. Inter- and intra-observer agreements were assessed by the intraclass correlation coefficient (ICC). The relationship between the two measurement methodologies was determined by Spearman's correlation coefficient and Bland-Altman plots. Discriminative capacity was calculated by using receiver operating curve (ROC) analyses in the whole cohort and age sub-groups above and below 45 years.

RESULTS

We found perfect inter-observer (ICC >0.96) and intra-observer (ICC >0.97) reliabilities for CSA measurements obtained from the standard AP radiographs and the 3D-CT. There was a strong correlation between the two methods (r = 0.960, P < 0.001). The mean CSA was 31.7° ± 4.2° in the standard AP radiographs and 31.8° ± 4.4° in the 3D-CT (mean difference 0.02°, P = 0.940; bias 0.02°, limits of agreement -2.29° to +2.33°). ROC analysis of the whole cohort showed that the CSA measured in the standard AP radiographs (area under the ROC curve [AUC] = 0.812, P < 0.001) and the 3D-CT (AUC = 0.815, P < 0.001) predicted RCT with high confidence. ROC analysis of patients aged ≥45 years showed that the CSA measured from the standard AP radiographs (AUC = 0.869, P < 0.001) and the 3D-CT (AUC = 0.870, P < 0.001) were very good at predicting RCTs.

CONCLUSION

CSA measured from standard AP radiographs and 3D-CT showed high consistency, and the CSA could be accurately and reliably measured using 3D-CT. CSAs measured from standard AP radiographs and 3D-CT could predict RCTs, especially in patients aged ≥45 years.

Mid-term effects of two different Kinesio tape treatments in female patients with subacromial impingement syndrome: Randomized controlled ultrasonographic study

STUDY DESIGN

Randomized controlled study.

PURPOSE OF THE STUDY

To evaluate the effect of Kinesio Tape (KT) applied differently in patients diagnosed with Subacromial Impingement Syndrome (SIS) on acromiohumeral distance (AHD) and supraspinatus tendon (SsT) thickness using ultrasound (US) and its effect on pain, upper limb functional status and hand grip muscle strength in the short and mid-term.

METHODS

The 90 patients diagnosed with unilateral SIS by clinical examination were randomized into 3 groups. In addition to exercise therapy, the deltoid in group 1 and the supraspinatus muscle in group 2 were taped from insertion to origin. Group 3, which was the control group, was applied 9 sessions of sham taping for 3 weeks. Cases were evaluated for AHD and SsT thickness, pain was evaluated with the Visual Analog Scale (VAS), function with the Disabilities of the arm, shoulder and hand (DASH) and the Western Ontario Rotator Cuff Index (WORC), and hand grip strength (HGS) using a dynamometer before, and 3rd week and 3rd month after the KT application.

RESULTS

There was a significant improvement in all parameters in the short and mid-term intra group comparisons in Group 1 and 2 after taping (P < .05). In intergroup comparisons, significant improvement was achieved in all parameters in Group 1 and Group 2 in the mid and short term compared to the control group (P < .05). In comparison of Group 1 and Group 2, HGS in the short term (p: 0.07) and the SsT thickness in the short and mid-term (p: 0.36, p: 0.85) did not exhibit any difference. The improvement in all other parameters in group 1 was statistically significant.

CONCLUSION

The findings of our study provide definitive evidence for the effectiveness of KT treatment depending on the method of tape application employed.

Subacromial Motion Metrics in Painful Shoulder Impingement: A Dynamic Quantitative Ultrasonography Analysis

OBJECTIVES

To explore the subacromial motion metrics in patients with and without subacromial impingement syndrome (SIS) and to investigate whether the abnormality was associated with rotator cuff pathologies.

DESIGN

This cross-sectional observational study used dynamic quantitative ultrasonography imaging for shoulder joint assessment.

SETTING

Outpatient rehabilitation clinic.

PARTICIPANTS

Individuals with SIS on at least 1 shoulder (n=32) and asymptomatic controls (n=32) (N=64).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Frame-by-frame, the humeral greater tuberosity against the lateral edge of the acromion was traced to obtain the minimal vertical acromiohumeral distance (AHD). The rotation angle and radius of the humerus were computed using the least-squares curve fitting method.

RESULTS

Approximately two-thirds of the shoulders with SIS did not have any sonographically identifiable rotator cuff pathologies. There was a consistent trend of nonsignificantly increased humeral rotation angles in painful shoulders. The generalized estimating equation demonstrated that the decreased minimal vertical AHD was associated with painful subacromial impingement (β coefficient: -0.123cm, 95% confidence interval [CI], -0.199 to -0.047). The area under the curve for the minimal vertical AHD to discriminate painful or impinged shoulders ranged from 0.624-0.676. The increased rotation angle (β coefficient: 10.516°; 95% CI, 3.103-17.929) and decreased rotation radius (β coefficient: -2.903cm; 95% CI, -5.693 to -0.111) were shown to be significantly related to the presence of supraspinatus tendinopathy.

CONCLUSIONS

Shoulders with SIS were characterized by a decreased minimal vertical AHD during dynamic examination. Abnormal subacromial metrics can develop in patients with mild (or no) rotator cuff pathologies. More prospective cohort studies are warranted to investigate the changes in subacromial motion metrics in populations at risk for painful or impinged shoulders.

Computer Image-Guided Precise Acromioplasty for Reducing the Critical Shoulder Angle

The shoulders with critical shoulder angle (CSA) of greater than 33-35° are associated with rotator cuff tears, whereas a CSA of less than 30° is likely to be osteoarthritic. However, anterior acromioplasty or lateral acromioplasty could not reduce high CSAs to the desired range (30-33°), with satisfactory accuracy and efficacy. Thus, we introduce a computer image-guided precise acromioplasty (CIG-PAP) technique, an individualized treatment based on three-dimensional planning. We believe that the introduction of this technique will provide an alternative approach to reduce a large CSA to the desired range (30-33°).

Optimization of the Grashey View Radiograph for Critical Shoulder Angle Measurement: A Reliability Assessment With Zero Echo Time MRI

Background:

Suboptimal positioning on Grashey view radiographs may limit the prognosticating potential of the critical shoulder angle (CSA) for shoulder disorders.

Purpose:

To investigate whether radiography optimized according to the latest research is reliable for measuring CSA in comparison with magnetic resonance imaging (MRI) featuring 3-dimensional (3D) zero echo time (ZTE) sequencing, which accentuates the contrast between cortical bone and surrounding soft tissue with high fidelity.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

Patients with shoulder pain were prospectively and consecutively enrolled. All patients had Grashey view radiographs as well as 3.0-T MRI scans with isotropic 3D ZTE sequencing. Acceptable positioning on the radiographs was determined using the ratio of the transverse to longitudinal (RTL) diameter of the lateral glenoid outline; radiographs with an RTL ≥0.25 were repeated. Two observers independently measured the CSA on the radiographs and the coronal oblique reformatted ZTE images, the latter including verification of measurement points by cross-referencing against images from other planes. Reliability of measurements between observers and modalities was analyzed with the intraclass correlation coefficient (ICC). The paired-samples t test was used to compare the differences between imaging modalities.

Results:

Enrolled were 65 patients (35 female and 30 male; mean age, 40.2 years; range, 25-49 years). Radiographs with optimal positioning (RTL < 0.25) were attained after a mean of 1.6 exposures (range, 1-4); the mean RTL was 0.09 (range, 0-0.20). Interobserver agreement of CSA was excellent for radiographs (ICC = 0.91; 95% CI, 0.84-0.94) and good for ZTE MRI scans (ICC = 0.85; 95% CI, 0.71-0.92). Intermodality agreement of CSA between radiographs and ZTE MRI scans was moderate (ICC = 0.66; 95% CI, 0.48-0.73). The CSA was significantly different between an optimal radiograph (30.7° ± 4.3°) and ZTE MRI scan (31.8° ± 3.8) (P = .005). Subgroup analysis revealed no significant differences in CSA measurement between ZTE MRI scans and Grashey view radiographs with an RTL of <0.1 (P = .08).

Conclusion:

CSA measurement on ZTE MRI scans with anatomic point cross-referencing was significantly different from that on Grashey view radiographs, even with optimal positioning, and radiography may necessitate more than 1 exposure. An RTL of <0.1 ensured reliability of radiographs when other standards of sufficient x-ray exposure were met.

Evaluation of anatomical variations with morphological measurements and their relationship with rotator cuff tear and acromion types

Introduction: There many more anatomical measurements such as the acromiohumeral distance and lateral acromion angle and acromial configuration was reported as might be associated with rotator cuff tear. In our study, we aimed to reveal the effect of acromion index, acromiohumeral distance, lateral acromion angle, critical shoulder angle values and the acromion type in the development of rotator cuff tear. Material and Method: In our retrospective study, 58 patients and 29 asymptomatic volunteers who underwent shoulder magnetic resonance imaging examinations were examined. acromion index, acromion humaral distance, lateral acromion angle and critical shoulder angle were measured and their relationship with rotator cuff tear and acromion types were evaluated. Results: Type III (hooked) of acromial shapes, higher acromion index and critical shoulder angle values, lower acromiohumeral distance and lateral acromion angle values are more frequently seen in rotator cuff tear patients, in our study. Conclusion: Thus, we revealed anatomical malformations that predispose to rotator cuff tear concerning the shoulder joint.

Added value of combined acromiohumeral distance and critical shoulder angle measurements on conventional radiographs for the prediction of rotator cuff pathology

Purpose

Method

Results

Conclusions

•

Acromiohumeral distance (AHD) and critical shoulder angle (CSA) do not depend on age or sex.

•

CSA and AHD are significantly different in healthy and pathologic rotator cuffs.

•

Combining CSA and AHD into one index (PI_AHD-CSA) increases overall diagnostic performance.

•

A high PIAHD-CSA increases the risk of full thickness rotator cuff tear and critical fatty degeneration.

Evaluation of bilateral acromiohumeral distance on magnetic resonance imaging and radiography in patients with unilateral rotator cuff tears

INTRODUCTION

The aim of this study was to evaluate the difference in the acromiohumeral distance (AHD) between the shoulders with full-thickness rotator cuff tear and contralateral healthy shoulders of the same patients on magnetic resonance imaging (MRI) and radiograph.

MATERIALS AND METHODS

We included 49 patients with unilateral full-thickness rotator cuff tears. The mean age of the patients (29 women and 20 men) was 54.57 ± 7.10 years. The shoulders were divided into those with a full-thickness rotator cuff tear and healthy shoulders. The mean AHDs on radiograph and MRI were calculated by two radiologists experienced in the musculoskeletal system. Shoulders with rotator cuff tears on coronal plane and sagittal MRI were divided into 3 (Patte I, II, III) and 4 subgroups (S: superior, AS: anterosuperior, PS: posterosuperior, APS: anteroposterosuperior), respectively. The relationship between the groups and the subgroups was statistically investigated.

RESULTS

The mean AHDs on radiograph were 6.93 and 9.11 mm and on MRI were 5.94 and 7.46 mm in the patient and control groups, respectively. The mean AHDs were 6.47, 6.03, and 4.95 mm in Patte I, II, and III, respectively. The difference between the subgroups was statistically significant. According to the sagittal plane topography, the mean AHDs (mm) were 6.39, 6.44, 5.8, and 4.6 mm in the superiorly, anterosuperiorly, posterosuperiorly, and anteroposterosuperiorly localized lesions, respectively. The relationship between S and AS was not statistically significant, and those between S and PS, AS and PS, S and APS, and PS and APS were significant.

CONCLUSIONS

In patients with unilateral full-thickness rotator cuff tear, AHD narrowing was observed on the törnekler side after evaluating the bilateral acromiohumeral distance on MRI and radiograph. AHD was significantly reduced by increasing the degree of supraspinatus tendon retraction in the coronal plane MRI and by the posterosuperior and anteroposterosuperior location of the rotator cuff tear in the sagittal plane MRI.